On his Blogger.com profile page, Twitter co-founder Evan Williams describes himself as "a farm boy from Nebraska, who's been very lucky in business and life". That luck seemed to be running out in recent months, when Twitter - the microblogging and messaging service created by Jack Dorsey, Biz Stone and Williams himself - struggled to cope with massive growth.

Instead of their Tweets, users were frequently seeing the "fail whale": a cute cartoon whale being lifted into the sky by a flock of birds. It was Twitter's way of saying: "Sorry, we're suffering a bit of downtime." But it became an emblem of the site's inability to cope.

Things are better now. The outages are fewer and further between than they were. And the company has just acquired Summize, the third-party startup that created a better Twitter search.

Whale of a time

During the bad spell, when the fail whale popped up almost every other day and became an internet meme in its own right, the criticism thrown at Twitter the company, and at Williams the person, was very fierce indeed.

What was it like to be working at Twitter through all that? Looking back at those months - most of the first half of 2008 - Williams and Dorsey are thoughtful, considerate of the users, and don't sound at all bitter.

"It didn't feel great, to be honest," sighs Dorsey. "We have extremely patient and forgiving users, which has been a big help. But we are all users of the service ourselves, so are all our friends and families. We are all feeling the pain and the frustration. It creates a lot of pressure on everyone here. It's not the healthiest way to exist, to be in crisis mode all the time."

Williams, too, is always thinking of the users. Even the most critical ones. He likes to see things from their point of view. "The level of criticism has been very intense at times," he says. "You try to remember the reasons for that. It's a cliché, I know, but people wouldn't be so critical if they didn't care. And that's reassuring, in a way.

"Twitter is a tool for one-to-many messaging. Some of the people it affects are people who like to make a lot of friends online. So it might amplify those users' frustrations more than other tools."

In the past two or three weeks, though, the outages have faded away. They still happen, yes, but less frequently and for much shorter periods of time. The Twitter developers, a small team of 12 prior to the Summize purchase, have been at work messing with Twitter's insides. Dorsey admits it's not over yet.

Cumulative effects

"We haven't solved all the problems, we still have a lot of work to do," he says. "But we did put some technology in place to track the causes of the outages, and some of that is paying off right now. We have a much better sense of how we need to fix things. Much of it consists of small changes that have a larger, cumulative effect on the system."

The Summize acquisition (neither party will say how much money changed hands) means Twitter gets more than a search tool. It also gets a team of developers much admired by Williams and Dorsey - an injection of new blood and fresh ideas. Summize co-founder (and former System Architect for AOL) Greg Pass becomes Twitter's new director of engineering and operations. The rest of the Summize development team will be moving to San Francisco to work in the Twitter office.

"We are sure that the guys behind Summize are world-class engineers," says Dorsey. "We went to meet them and got along really well. They built a good search tool, and we could see that they were great curators of that technology."

Search matters, he adds. The Twitter plan always included it. But the Summize team built a better search first.

"Search is a big part of the product. There's a lot of value for people in sharing stuff with their friends. Search lets people go deeper into what other people are doing; it means you can recognise the pulse." Those critics - fewer of them, now, but they're still around - were quick to say buying Summize was foolish. Why not invest in getting the core service stable, before going on a corporate shopping spree? Williams sounds slightly exasperated. "We have already seen criticisms like that, but they are too simplistic. These are two completely different things - service stability and investment in growth. And we had already implemented systems to reduce the outages, weeks ago, which have had a positive effect.

"The Summize guys are great engineers and I'm sure they will help us improve stability, yes." But that wasn't the reason for the purchase. And Williams is looking much further ahead. "This is our first acquisition. We are going to let things settle down for a bit. We want to be discerning, to pace ourselves."

He's confident that the fail whale is going to fade from view. Perhaps not immediately, but given time. Unlike many of the critical bloggers, Williams likes to think far beyond the next 24 hours.

"We can scale further. It will be an ongoing process of optimising and iterating. Lots of little steps. Some big ones."

Capital ideas

Of course, that far future is dependent on another important factor: money. Twitter does not yet earn any (the company is "pre-revenue", as Williams puts it), and while it has plenty of venture capital investment in the bank (to pay for what Williams calls "the usual startup stuff: salaries, servers, rent"), there will need to be an income eventually.

Again, unlike his critics, Williams sees no need to rush things. He's toying with many ideas for making money and is keen to adopt something that stems directly from the functionality Twitter provides, rather than simply slapping banner adverts on top of its web pages. Might Twitter start acting as a bank for small payments between users, for example?

"We don't have any specific plans for a payment system, though that's interesting. But we definitely are striving for (and believe we can achieve) a built-in revenue model that is compatible with the open nature of Twitter and its ecosystem, rather than something tacked-on."